This invention relates generally to the field of mailing machines, and more particularly to components of mailing machines that correct a skewed orientation of mailpieces introduced into the mailing machines.
Generally, a mailpiece transport on a mailing machine transports envelopes and other mailpieces along a feed path so that various functions may be performed on the mailpiece at different locations along the feed path. For example, at one location along the feed path the mailpiece may be weighed, at another location the mailpiece may be sealed, and at a further location an indicia for postage may be applied to the mailpiece. Drive rollers and/or drive belts may be employed to contact the mailpiece to propel the mailpiece along the feed path. In some mailing machines mailpieces may be fed by hand one-by-one into an infeed end of the mailing machine. When this occurs, the length axis of the mailpiece may be skewed from the direction of the feed path. Feeding of a skewed mailpiece through the feed path may have undesirable consequences, such as jams, failure to properly seal the mailpiece, or failure to properly print on the mailpiece.
It is known to provide a mailpiece deskew mechanism at the infeed end of a mailing machine to align the mailpiece length axis with the direction of the feed path. However, in some cases a mailpiece may slip or stall, and therefore fail to be properly fed, at the deskew mechanism. This is particularly likely to occur if the mailpiece is “puffy” due to improper folding of an insert (e.g. a letter) within the mailpiece envelope.
It is often required that mailing machines be capable of handling both thick and thin mailpieces. To cope with this requirement, rather complicated deskew mechanisms have been provided. In particular, a deskew finger that is part of the deskew mechanism may be biased downwardly toward a feed deck by using both a relatively light spring and a relatively heavy spring. The light spring keeps the deskew finger in contact with the feed deck with a relatively light force that allows thin mailpieces to pass through the deskew mechanism. If a thick mailpiece is fed through the deskew mechanism, the deskew finger is deflected upwardly by a sufficient amount to bring the heavier spring into action. The heavier spring causes a sufficiently strong normal force to be applied between the thick mailpiece and a drive roller of the deskew mechanism so that the thick mailpiece can be properly fed.
As an alternative, a single relatively light spring may be used in the deskew mechanism, with a second drive nip provided just downstream from the drive roller of the deskew mechanism.
Another problem that may be encountered with a deskew mechanism is noise generated when the deskew finger returns to contact with the feed deck after a thick mailpiece passes through the deskew mechanism. The feed deck may be hollow and may reverberate in response to the deskew finger coming into contact with the feed deck